Ploopy Mini open-sourced
The Ploopy Mini Trackball by crop_octagon is now completely open-source. All design files are available, and it runs QMK.
Published June 18, 2021
All of the design files are available on GitHub. STEP files, STL files, electronics files for making PCBs, and firmware (QMK, of course).
You can also find complete assembly instructions, here!
If you don't have a 3D printer, you can find kits here.
Published on Fri 18th Jun 2021. Featured in KBD #31 (source).